diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -663,6 +663,8 @@
 - Correcly diagnose jumps into statement expressions.
   This ensures the behavior of Clang is consistent with GCC.
   (`#63682 <https://github.com/llvm/llvm-project/issues/63682>`_)
+- Remove redundant dump of BlockDecl's ParmVarDecl
+  (`#64005 <https://github.com/llvm/llvm-project/issues/64005>_`)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/clang/include/clang/AST/ASTNodeTraverser.h b/clang/include/clang/AST/ASTNodeTraverser.h
--- a/clang/include/clang/AST/ASTNodeTraverser.h
+++ b/clang/include/clang/AST/ASTNodeTraverser.h
@@ -104,7 +104,8 @@
         Visit(Comment, Comment);
 
       // Decls within functions are visited by the body.
-      if (!isa<FunctionDecl>(*D) && !isa<ObjCMethodDecl>(*D)) {
+      if (!isa<FunctionDecl>(*D) && !isa<ObjCMethodDecl>(*D) &&
+          !isa<BlockDecl>(*D)) {
         if (Traversal != TK_AsIs) {
           if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(D)) {
             auto SK = CTSD->getSpecializationKind();
diff --git a/clang/test/AST/ast-dump-decl-json.m b/clang/test/AST/ast-dump-decl-json.m
--- a/clang/test/AST/ast-dump-decl-json.m
+++ b/clang/test/AST/ast-dump-decl-json.m
@@ -1924,31 +1924,6 @@
 // CHECK-NEXT:              ]
 // CHECK-NEXT:             }
 // CHECK-NEXT:            ]
-// CHECK-NEXT:           },
-// CHECK-NEXT:           {
-// CHECK-NEXT:            "id": "0x{{.*}}",
-// CHECK-NEXT:            "kind": "ParmVarDecl",
-// CHECK-NEXT:            "loc": {
-// CHECK-NEXT:             "offset": {{[0-9]+}},
-// CHECK-NEXT:             "col": 9,
-// CHECK-NEXT:             "tokLen": 1
-// CHECK-NEXT:            },
-// CHECK-NEXT:            "range": {
-// CHECK-NEXT:             "begin": {
-// CHECK-NEXT:              "offset": {{[0-9]+}},
-// CHECK-NEXT:              "col": 5,
-// CHECK-NEXT:              "tokLen": 3
-// CHECK-NEXT:             },
-// CHECK-NEXT:             "end": {
-// CHECK-NEXT:              "offset": {{[0-9]+}},
-// CHECK-NEXT:              "col": 9,
-// CHECK-NEXT:              "tokLen": 1
-// CHECK-NEXT:             }
-// CHECK-NEXT:            },
-// CHECK-NEXT:            "name": "y",
-// CHECK-NEXT:            "type": {
-// CHECK-NEXT:             "qualType": "int"
-// CHECK-NEXT:            }
 // CHECK-NEXT:           }
 // CHECK-NEXT:          ]
 // CHECK-NEXT:         }
diff --git a/clang/test/AST/ast-dump-decl.m b/clang/test/AST/ast-dump-decl.m
--- a/clang/test/AST/ast-dump-decl.m
+++ b/clang/test/AST/ast-dump-decl.m
@@ -142,12 +142,17 @@
 
 void TestBlockDecl(int x) {
   ^(int y, ...){ x; };
+  int z;
 }
 // CHECK:      FunctionDecl{{.*}}TestBlockDecl
 // CHECK:      BlockDecl {{.+}} <col:3, col:21> col:3 variadic
 // CHECK-NEXT:   ParmVarDecl{{.*}} y 'int'
 // CHECK-NEXT:   capture ParmVar{{.*}} 'x' 'int'
 // CHECK-NEXT:   CompoundStmt
+// CHECK-NEXT:     ImplicitCastExpr
+// CHECK-NEXT:       DeclRefExpr{{.*}} 'x'
+// CHECK-NEXT: DeclStmt
+// CHECK-NEXT:   VarDecl{{.*}} z
 
 @interface B
 + (int) foo;